Von Willebrand disease is a congenital deficiency of von Willebrand factor (VWF) that results in platelet dysfunction. It is usually characterized by mild bleeding. Screening shows prolonged bleeding time, normal platelet counts, and possibly a slight increase in partial thromboplastin time.
Thrombotic thrombocytopenic purpura and hemolytic uremic syndrome are acute, fulminant diseases characterized by the development of thrombocytopenia and microangiopathic hemolytic anemia.
Idiopathic (immune) thrombocytopenic purpura is a hemorrhagic disorder caused by thrombocytopenia not associated with a systemic disease. It is usually chronic in adults but is often acute and transient in children. The spleen is normal in size.
Hereditary intracellular platelet disorders are rare diseases and result in lifelong bleeding. Diagnosis is confirmed by platelet aggregation testing. If bleeding is severe, platelet transfusions are necessary.
Platelets are fragments of megakaryocytes that provide hemostasis of circulating blood. Thrombopoietin is synthesized by the liver in response to a decrease in the number of bone marrow megakaryocytes and circulating platelets and stimulates the bone marrow to synthesize platelets from megakaryocytes.
Consequences of lymphopenia include the development of opportunistic infections and an increased risk of cancer and autoimmune diseases. If lymphopenia is detected during a complete blood count, diagnostic tests for immunodeficiency conditions and lymphocyte subpopulation analysis are necessary. Treatment is aimed at the underlying disease.
Neutropenia (agranulocytosis, granulocytopenia) is a decrease in the number of neutrophils (granulocytes) in the blood. With severe neutropenia, the risk and severity of bacterial and fungal infections increases.
Because of the high incidence of HbS thalassemia and beta thalassemia in certain population groups, congenital presence of both anomalies is quite common.
Symptoms and complaints are due to the development of anemia, hemolysis, splenomegaly, bone marrow hyperplasia and, with multiple transfusions, iron overload. Diagnosis is based on quantitative hemoglobin analysis.
